Some industrial cleaning operations, such as the cleaning of bottles or cleaning in place, can result in the formation of a significant degree of foam. It is due in particular to the presence of food stains or of sticky residues present on the bottles. For the purpose of decreasing or even preventing the formation of this foam, it is known to add one or more defoaming surfactants to the cleaning composition. These defoaming surfactants are generally of the non-ionic type.
One of the subject-matters of the present invention consists of novel surfactant compositions which are derived from alkylpolyglycosides.
Alkylpolyglycosides are well-known non-ionic surfactants. Their manufacturing process is disclosed, for example, in Patent Application EP-A-0 077 167.
However, to date, it is impossible to use surfactant compositions based on alkylpolyglycosides which are devoid of water or devoid of fatty alcohol. This is because the very high melting temperatures of alkylpolyglycosides do not allow them to be handled in anhydrous form. They are therefore diluted in water or presented as a mixture with one or more fatty alcohols.
Patent Application EP-A-0 489 777 discloses antifoaming compositions comprising alkylpolyglycosides in which the alkyl chain comprises from 6 to 12 carbon atoms.
German Patent Application No. DE 38 35 199 discloses alkylpolyglycosides blocked by an arylmethyl or alkyl radical exhibiting antifoaming properties.
However, it is clear to a person skilled in the art that the blocking reaction employed in this publication cannot be applied to the many blocking reagents which decompose in water. In another aspect of the present invention, the Applicant Company has therefore sought to develop a novel blocking process which involves anhydrous intermediates which are devoid of fatty alcohols.